Electrical impulse generator



April 21, 1931.. R. H. PARK 1,8 8

ELECTRICAL IMPULSE GENERATOR Filed Dec. 17, 1827 Fig I Fig 2 Time Figs 2 5g 1 Time Inventov:

Robert H Park Has Attorney the appended claims.

Patented Apr. 21, 1931 UNITED STATES PATET OFFICE ROBERT E. PARK, 0F SC'OTIA, NEW YORK, ASSIGNOB To GENERAL ELECTRIC COMPANY,

A CORPORATION or NEN'YORK ELECTRICAL nvirunsn GENERATOR Application filed. December 17, 1927. Serial No. 240,906.

My invention relates to the production of electrical impulses and has for its princlpal object the provision of an improved apparatus and method of operation whereby electrical impulses of different characteristics may be readily produced.

Various means have been utilized in the past for subjecting electrical apparatus to electrical disturbances similar to those encountered under actual working conditions. It is desirable that such means be capable of varying the characteristics of the impulses to which the apparatus is subjected. Thus in the case of a high voltage impulse generator, for example, it is desirable that both the magnitude and the wave shape of the voltage impulses be capable of adjustment. In accordance with my invention, these results are produced by an electrical impulse generator wherein the magnitude of the impulse is determined by the rate of change in the current transmitted through the arc of a vapor electric device and the wave shape of the impulse is determined by the characteristics of the circuits associated with the vapor electric device.

My invention will be better understood from the following description when considered in connection with the accompanying drawings and its scope will be pointed out in Referring to the drawings, Fig. 1 illustrates an impulse generating apparatus wherein my invention has been embodied; and Figs. 2 and 3 relate to the operation of the apparatus illustrated by Fig. 1.

This apparatus comprises a vapor electric arc device 1 connected to supply terminals 2 through a resistor 3 and a plurality of parallel connected circuits which respectively include an adjustable resistor 4, an adjustable capacitor 5 and a reactor 6. The electrical impulses produced by the generating apparatus are applied through the terminals 7 to the apparatus by which they are utilized. A switch 8 is arranged to short circuit an adjustable portion of the resistor 3.

Assuming the terminals 2 to be connected to a suitable source of power, the switch 8 to be closed and adjustment of the resistor 3 to be as illustrated, an electrical impulse of predetermined characteristics is produced at the terminals 7 of the apparatus by opening of the switch 8. It has been found that the magnitude of this impulse is dependent on the rate at which the current ofthe arc of the device 1 decreases to zero and that the wave shape-of this impulse is dependent on the'ad justment of the resistor 4.

Thus if the adjustment of the resistor 3 is such that opening of the switch 8 causes the arc current to start to decrease at the instant a as indicated by Fig.2, an impulse of comparatively small magnitude will be produced for the reason that although the current is suddenly decreased to the point where the arc normally tends to be unstable, the ionized gas or vapor; within the device 1 tends to prevent interruptionfof the arc until itscurrent has decreased to a comparatively low value. 7 1 j a.

If the adjustment of the resistor 3 is such that opening of the, switch 8 produces a smaller decrease in the arc current as indi-' cated by Fig. 3, however, the arc does not snap out until the vessel of the device 1 is deionized. Under these conditions, an'irnppulse of greater magnitude is produced by interruption of the arc for the reason that snapping oithe arc is more abrupt.

. Itwill be apparent in view of the foregoing explanation that the mangitude of the current interruptedby snapping of the arc is. readily determined-by adjustment of the resistor 3. It-will readily be understood by those skilled in the art that'the wave form of the impulses produced at the terminals 7 is dependent on .the damping effect of the re sistor 4 on the oscillations produced in the oscillatory circuit including the capacity 5 and the inductance 6 by snapping of the arc of the device 1. The embodiment of the invention illustrated anddescribed herein has been selected io-r the purpose of clearly setting forth the principles involved. It will be apparent, however, that the invention is susceptible of being modified in various respects to meet the difierent conditions encountered in its use and I therefore aim to cover by the appended claims all modifications within the ing the wave shape of oscillations set up true spirit and scope of my invention. therein.

What I claim as new and desire to secure In witness whereof I have hereunto set by Letters Patent of the United States is: my hand this 16th day cf December, 1927. 5 An impulse generating apparatus in- ROBERT H. PARK.

eluding an oscillatory circuit, a mercury arc device, means connected to said device through said circuit for adjusting the magnitude of the current to a value at which the are of said device is interrupted, and means 7 connected to said oscillatory circuit for adjusting the wave form of the oscillations produced therein by the interruption of said are.

2. An impulse generating apparatus in- 15 eluding an oscillatory circuit, a mercury vapor discharge device, means connected to said device through said circuit for adjusting the magnitude of the current to a'value at which the discharge of said device is inm terrupted, and an adjustable resistor connected in shunt to said oscillatory circuit for redetermining the wave form of the oscil ations produced in said circuit by interruption of said are. as 3. In an impulse generating apparatus,

the combination of a vapor electric discharge device, an oscillatory circuit connected with said device, adj ust-able means connected in shunt to said oscillatory circuit for 30 controlling the wave shape of oscillations set up in said circuit by interruption of current thru said device, means connected with said device thru said oscillatory circuit for supplying operating current to said device, and 36 means for adjusting said current between a value at which the flow of said current is maintained and a value at which said device may become deionized to interrupt the fiow of said current, when said supplying means 40 is energized. 5

4. In an impulse generating apparatus, the combination of a vapor electric discharge device, an oscillatory circuit connected in series with said device, said circuit including 45 an inductance and output terminals connected with said inductance, a variable resistor connected in shunt to said oscillatory circuit, means connected with said device thru said oscillatory circuit for supplying op- 50 crating current to said device, and adjustable means in said connection for controlling said operating current.

5. In an impulse generating apparatus, the combination of a vapor electric discharge 5a device, means for supplying operating cur- I rent to said device, said means including a supply circuit connected in series with said device, an adjustable resistance in said circuit, an inductance in said circuit, a con- 80 denser connected in shunt to said inductance I25 whereby an oscillatory circuit is provided thereby, means connected with said oscillatory circuit for receiving osciliations therefrom, and adjustable means connected, in a shunt to said oscillatory circuit for chang- 

